Safety percussion fuse



Mar. 3, 1925.

L. w. ROCKWELL SAFETY PERCUSSION FUSE Filed Feb 9, 1925 rlulll INVENT R.

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Patented Mar. 3, 1925.

LEA W. ROCKWELL, O'F PLAINVILLE, CONNECTICUT.

SAFETY PERCUSSION FUSE.

Application filed February 9, 1923.

To all whom it may concern:

Be it known that I, LEA IV. ROCKWELL, a citizen of the United States, residing in Plainville, in the county of Hartford and State of Connecticut, have invented-a new and Improved Safety Percussion Fuse, of which the following is a specification.

My invention relates more especiallyto that class of fuses employed to ignite'the explosive matter in high explosive shells, and an object of my invention, among others, is to provide a device of this class that will not effect its purpose prematurely or unintentionally; and a further object of the invention is to provide a device of this class that shall, with a maximum degree of certainty, effect its purpose at the proper time.

A form of fuse embodying my invention and in the construction and use of which the objects herein set out, as well as others, may be attained, is illustrated in the accompanying drawings, in which Figure 1 is a view in central longitudinal section through a fuse embodying my invention, the outlines of a shell being shown by dotted lines.

Figure 2 is a view in cross section through my improved shell on plane denoted by dotted line 2-2 of Figure 1.

In the accompanying drawings the numeral 3 indicates a fuse body that is attached within the base of a shell 4 in any ordinary manner, screw threads being commonly employed and being shown herein for this pur pose. This body has a chamber therein closed at one end and opening at the other end of said body, and comprising a hammer chamber and a cartridge chamber. A hammer 5 is slidably mounted in that part of said chamber comprising the hammer chamber 6 and a hammer stop 7 is located in the path of the hammer to limit its striking movement.

In the form of the device as illustrated herein this hammer stop is in the form of a ring fitting the screw threaded wall of the cartridge chamber 8 that opens out at the mouth of the body, this ring being of a size to project beyond the walls of the chamber 6 at the mouth thereof to constitute the stop above mentioned.

A primer cartridge is located within the chamber 8, this cartridge comprising a cartridge shell 9 having its outer surface screw threaded to fit the screw threaded surface of the wall of the chamber 8. A percussion Serial No. 618,138.

cap 10 is located at one end of the cartridge shell 9, and the chamber within the shell is filled with any suitable explosive material 11 that may be retained in place by a wad 12.

The interengaging threads between the cartridge shell 9 and the chamber 8 are of a size to permit free rotation of the cartridge shell within the chamber, the fit of the threads, however, not being sufficient to permit any undue movement of the cartridge shell lengthwise within said chamber. The cartridge shell is moved within the chamber 8 to place the percussion cap 10 in position to be struck by a point 13 on the hammer 5, this movement being effected by the rotation of the shell 4 imparting the same movement to the fuse body 3, this rotation being caused by the rifling within the barrel of the gun within which the shell is fired, and such rotation, owing to the inertia of the cartridge shell 9, will cause the fuse body 3 to rotate slightly faster than the cartridge shell with a result that the latter will be screwed backwarolly within the chamber 8 until the percusslon cap is in position to be struck by the point 13, the direction of the thread being such as to cause this backward move ment of the cartridge shell.

In order to retain the cartridge shell in its unarmed position and prevent movement therefrom so that there will be no danger of premature explosion of the shell by reason of being dropped or otherwise jarred, I employ a locking pin 14 extending across the joint between the fuse body and cartridge shell, in the structure herein shown this pin passing entirely through said parts and being secured in place in any suitable manner, as by heading. This pin is of a size and of such material that it will be sheared off by the torsional force applied to the body 3 and the resistance to such force caused by the inertia of the cartridge shell 9. It will thus be seen that the locking pin 14 cannot be broken or severed except by a sudden torsional force, which force it will be practically impossible to apply to the shell except in the firing operation in a gun. Practically every liability to danger from premature explosion of the shell is removed by the employment of this locking pin in connection with the cartridge shell movable by reason of interengaging screw threaded parts.

In accordance with the provisions of the patent statutes, I have described the principles of operation of my invention to ether with the device which I now consider to represent the best embodiment thereof; but

I desire to have it understood that the device shown is only illustrative, and that the invention may be carried out by other means.

I claim- 1. A safety fuse comprising a fuse body,-

a hammer and a cartridge shell, one of which members has a movable thread-ed engagement with said body and the other of which is freely movable therein to place said hammer and shell in relatively armed positions, a stop rigid with said body to positively limit the movement of the threaded member with respect to the freely movable member and a locking member connecting said body and one of said members to be ruptured by forces caused by inertia of the cartridge shell opposing torsional force applied to said body.

2. A safety fuse comprisinga fuse body, a hammer freely movably mounted in the body,

a cartridge shell having threaded engagement with said body to, place it in armed position with respect to said hammer, and a locking member connecting said body and shell and arranged to be ruptured by force caused by the inertia of the cartridge shell opposing torsional force applied to said body.

3. A safety fuse comprising a fuse body having a hammer chamber at the inner end thereof, a hammer mounted for unrestricted sliding movement in said chamber, a cartridge shell having threaded engagementwitl-i said body in a chamber at the outerend thereof, means between said cartridge and hammer for determining the position of said cartridge under torsional force of the shell in flight, and a locking member connecting said body'and shell and arranged to be ruptured by forces caused by inertia of the shell opposing torsional force applied to said body.

LEA IV. ROCKIVELL. 

